Femoroacetabular Impingement (FAI)

The hip is a ball-and-socket joint. The rounded head of the upper femur (thighbone) fits firmly into the socket of the pelvis, and together they make up the hip joint. In newborns and children with developmental hip dysplasia (DDH), the hip joint has not formed normally and the ball of the femur is loose in the socket. This usually means the hip is very easily dislocated.

Causes and Risk Factors

DDH tends to run in families, and is more common in:

  • The left hip
  • Girls
  • Firstborn children
  • Babies born in the breech position
  • Family history of DDH
  • Oligohydramnios patients (low levels of amniotic fluid)

Symptoms

DDH is most often present at birth, though it may develop during the first year of childhood. Some babies born with DDH may not present any symptoms initially.

Common signs of DDH include:

  • Legs are different lengths
  • Uneven skin folds on the thigh
  • Less mobility or flexibility on one side
  • Limping, walking on the toes, or waddling gait

Treatment

When DDH is diagnosed at birth, it can usually be treated conservatively with good results. If the condition is not diagnosed until a child begins walking, treatment can be a little more complicated.

Nonsurgical treatment options include:

  • Harnesses to hold the hip in the proper position while allowing free movement of the legs
  • Bracing or casting are used if a firmer material is needed to keep the joint in the proper position

In some cases, the pediatric orthopedic surgeon will need to reposition your child’s femur into the right position, and apply a cast to hold the bones in place. This procedure is performed while the child is under anesthesia. Surgery to correct DDH is sometimes necessary to realign the hip.